Genital human papillomavirus (HPV) infection is one of the most
commonly diagnosed sexually transmitted infections world-wide. Over the
last two decades, research has established a strong causal link between
specific types of HPV infection and cancer, particularly cervical, anal,
vulvar/vaginal, penile, and oropharyngeal cancer. Limited
epidemiological studies of anogenital HPV infection have been conducted
in Hispanic populations (including Puerto Rico), and population-based
incidence and prevalence estimates of HPV infection among Hispanics are
limited. Studies that evaluate knowledge and awareness of HPV among men
are also scarce. With the world-wide introduction of two new
prophylactic vaccines against high-risk HPVs causing cervical cancer,
and the recent FDA approval of the quadrivalent vaccine in preventing
genital warts in men, there is an urgency to determine the burden of HPV
in Hispanic populations before vaccine programs are implemented on a
widespread basis. Knowledge and acceptability of the vaccine prior to
implementation of these programs are also necessary to allow a targeted
assessment. This review article summarizes existing research on HPV
infection and HPV-related morbidities in men, with a particular emphasis
on Hispanic men in the United States and Puerto Rico. Three major areas
are discussed: (1) genital warts, (2) HPV and related cancers and (3)
biobehavioral and psychosocial factors related to HPV infection and
vaccination. Specific recommendations for advancing HPV research and
knowledge among Hispanic populations also are suggested.

Infectious agents are among the few known causes of cancer I and
contribute to a variety of malignancies (1). One of these I infectious
agents is human papillomavirus (HPV), one of the most commonly diagnosed
sexually transmitted infections (STIs) world-wide (2) and a key causal
precursor for cervical cancer. HPV infection is considered the second
most important infectious agent related to cancer, just below
Helicobacter pylori. Overall, 5.2% of all cancers worldwide can be
attributed to HPV infection (3). The World Health Organization (WHO)
estimates that the prevalence of HPV infection is between nine and
thirteen percent or about 630 million people (2). An estimated 20
million are infected with HPV in the United States (US), with 6.2
million new diagnoses annually (4-5). While a majority of infections are
asymptomatic or self-limited, acquisition of specific types of HPV can
result in a significant economic burden with 418 million dollars of
estimated direct medical costs for non-cervical HPV types related
conditions in the US (6).

More than 100 HPV types have been identified with more than 30
being sexually transmitted (7). Anogenital HPV types have been
classified into low-risk types (non-oncogenic), which are associated
with anogenital warts (condyloma acuminata), oral and conjunctival
papillomas, recurrent respiratory papillomatosis (in infants and young
children), and mild dysplasia (8). High-risk types (oncogenic) are
associated with high-grade dysplasia and various cancers. Current
estimates of the attributable fraction, the proportion of cancer cases
preventable by the elimination of HPV, are very high (9): 100% for
cervical, 90% for anal, 40% for vulvar and vaginal, 50% for cancer of
the penis, and between 33 and 72% of oropharyngeal cancers (10).

Although there has been increasing interest in understanding the
burden of HPV infection and related comorbidities in men (11), studies
in this group are still quite limited (12), particularly among
Hispanics. Research and surveillance data have indicated that Hispanics
have been disproportionately affected by HIV/ AIDS (13), Other STIs (14)
and may engage disproportionately in high-risk sexual behaviors (15). In
addition, a higher incidence of cervical cancer is observed in Puerto
Rico and Hispanic women in the US compared with non-Hispanic whites
(Figure 1). These factors could reflect a potential higher prevalence of
HPV infection in these populations, as well as disparities in screening
rates in these groups (16) suggesting that Hispanic and Puerto Rican men
might also be at higher risk for HPV infection and related health
outcomes. This high incidence might also lead to a significant economic
burden. In Puerto Rico for example, it was estimated that the economic
impact of HPV related cancers in 2004 was approximately 7.5% (close to 5
million dollars) of the total cancer costs (17).

Even though HPV infection is highly prevalent in sexually active
men, (18), most research studies have focused only in women. Studies in
men are of particular relevance because, as with other STIs, men play a
key role in the transmission dynamics to both male and female sexual
partners. It is also clear that HPV infection in men is a serious
clinical issue, given the association of HPV infection with a variety of
cancers in men, including anal cancer and a subset of penile and oral
cancers (19).

With the world-wide introduction of two new prophylactic vaccines
(bivalent vaccine protecting against HPV 16 and 18, and the quadrivalent
vaccine protecting against HPV 16, 18, 6 and 11) against oncogenic HPVs
causing cervical cancer in women (20), and the recent FDA approval of
the quadrivalent vaccine to prevent genital warts also in men, there is
an urgency to determine the burden of HPV in Hispanic populations before
vaccination programs are implemented on a widespread basis. Knowledge of
the burden of the disease and its related morbidities prior to
implementation of these programs will allow a better assessment and
understanding of the short-term and long-term effectiveness of this
primary prevention strategy for cervical neoplasia and genital warts. In
addition, it will permit exploring the prevalence of type-specific HPVs
in these populations, not currently included in the HPV vaccines
available in the market.

The present article presents a review of the existing research
literature on HPV infection and HPV-related morbidities in men, with a
particular emphasis on Hispanic men (including Puerto Rico). Three major
areas are discussed: (1) genital warts, (2) HPV and related cancers and
(3) biobehavioral and psychosocial factors related to HPV infection and
vaccination. Specific recommendations for advancing HPV research and
knowledge among Hispanic populations are suggested, particularly as HPV
vaccination becomes widely available in this ethnic group.

[FIGURE 1 OMITTED]

I. Genital Warts

HPV frequently presents clinically as anogenital warts (condyloma
acuminata) in both males and females (21). More than 90% of genital
warts are associated with HPV types 6 and II, low-risk types that often
are associated with other clinical symptoms such as burning and bleeding
(10). Genital warts also can lead to psychosocial consequences such as
embarrassment, anger, shame, and can interfere with sexual relationships
(22). Genital warts are common in the US, with an estimated one million
incident cases each year (11). Estimates from the National Health and
Nutrition Examination Survey (NHANES) reported an overall prevalence of
genital warts between 1999-2004, of about 5.6% among sexually active men
and women aged 18-59 years old (23). The prevalence was higher in women
(7.2%) compared with men (4.0%). This disparity might be due to an
actual gender differences in the risk for acquiring warts, in their
diagnosis or recognition, limited access to health care or due to lack
of routine clinical screening of the genitalia among men. Significant
racial/ethnic differences were also observed, in which Mexican American
men had a self-reported prevalence of I. 7%; significantly lower than
non-Hispanic white (4.9%) and non-Hispanic black men (2.4%) (p-value
[less than or equal to] 0.05).

II. HPV and Cancer

Penile HPV Infection and Cancer

It is estimated that at least 40% of penile cancers are
attributable to HPV (24). The prevalence of HPV in penile tumors ranges
from 29% to 82% depending on the distribution of histopathologic types
in a given report. Oncogenic HPV 16 and/or 18 are the most common
genotypes detected in penile squamous cell carcinoma (SCC) (25).

Epidemiological studies have shown that the prevalence of penile
HPV infection varies by country (26), varying also in relation to the
population studied, and the area of the genitalia sampled (27). In
recent cross-sectional studies that have evaluated HPV infection in
Hispanic male populations including those in the military (28),
asymptomatic men (29), patients at vasectomy clinics (30), university
students (31), industry workers, men attending sexually transmitted
disease clinics (32) and husbands of women with cervical intraepithelial
neoplasia (CIN) grade III or invasive squamous cell carcinoma of the
cervix (33-34), prevalence estimates range from 8.7% to 50.9%. The
baseline prevalence of HPV reported in a group of healthy military
Mexican men was 34.8% for high-risk HPV and 23.9% for low-risk HPV (28).
In this study, the most common oncogenic HPV types detected in the penis
were HPV-59 (8.8%), followed by HPV-16 (6.0%), and HPV-52 (5.9%), while
the most common non-oncogenic types were HPV-84 (7.1%), HPV-6 (4.3%),
and HPV-54 (3.9%). Another study among asymptomatic men in the US (29)
reported that Hispanic ethnicity was independently associated with
oncogenic and nononcogenic HPV types as compared with being non-Hispanic
white.

In general, risk factors associated with penile HPV infection
include indicators of high-risk sexual behavior (18) such as lifetime
number of sex partners (26), number of recent sex partners (35), age at
first sexual intercourse (36) and sexual frequency (37). Additionally,
patterns of sexual networking in men are believed to be key to
understanding HPV transmission dynamics and are also especially
important for understanding risk of infection among their female
partners (38). The protective effect of condom use has been reported,
but transmission may still occur via unprotected areas of genital skin.

Epidemiological studies have identified circumcision as an
independent protective factor against genital HPV infection (18, 27,
39). Risk reduction of HPV infection among circumcised men in these
studies ranges from 60%-80%. Potentially important for understanding HPV
infection among Hispanic men is that Hispanics generally evidence lower
rates of circumcision compared to the population at large. For example,
NHANES reported that 79% of men in the US were circumcised (40), with
prevalence estimates much lower among Mexican American men (42%). A
recent population-based study in Puerto Rico estimated that the
prevalence of circumcision among adult men was 30.6% (41). Low
circumcision rates could leave Puerto Rican men at greater risk for HPV
infection, a possibility that highlights the importance of studying the
burden of HPV infection in this population. Also, recent studies have
evaluated the association between male circumcision and HPV infection
clearance and persistence (27, 42-43); suggesting that the higher
prevalence of HPV among uncircumcised men may be attributed to a longer
duration of infection rather than to a greater rate of acquisition.

Invasive SCC of the penis is relatively rare in the US and in
developed countries, accounting for less than 1% of malignancies among
men. An evaluation of cancer registries around the world shows that,
although penile cancer is a rare disease, it is particularly prevalent
in Uganda, Brazil, and Puerto Rico (44). Between 1998 and 2003, the
annual average age-adjusted incidence rate of penile cancer in the US
was 0.81 per 100,000 men, but was 72% higher in Hispanics relative to
non-Hispanics (45). In Puerto Rico, the rate of penile cancer is
considerably higher than in the general US population, at an approximate
4-fold ratio (46). In 2004, the annual age-adjusted (US population)
incidence rate of penile cancer in Puerto Rico was 2.21 per 100,000
(Figure 2).

Anal HPV infection and cancer

Anal HPV infection with oncogenic HPV genotypes is a key causal
precursor for anal cancer (47) and its precursor lesion known as anal
intraepithelial neoplasia (AIN). As with penile HPV infection, previous
estimates of the prevalence of anal HPV infection in men have varied
widely. A study among 1,200 men from Brazil, Mexico and the US reported
that anal HPV infection was common among men who acknowledge no lifetime
sex with other men (13.4%), while the prevalence was three times higher
among men who acknowledged sex with other men (43.2%). Subpopulations
such as men having sex with men (MSM) (48) and HIV-positive individuals
are at an event higher risk of HPV infection and anal cancer (49).

HIV status increases the risk for anal HPV infection and other
malignancies among MSM and bisexual men and women. Epidemiological
studies have documented that anal HPV infection is nearly universal
amongst HIV-positive MSM (50). Studies performed by Palefsky among MSM
in San Francisco showed that the prevalence of anal HPV infection was
93% among HIV-positive men and that 73% of these participants showed
more than one HPV type (51). In this study, a significant increasing
trend in the prevalence of HPV infection was observed as levels of CD4
decreased.

Even though Hispanics are disproportionally affected by HIV/ AIDS
(52) and represent one of the largest groups of MSM living with HIV/AIDS
in the US (53), few studies have examined the impact of HPV infection
among Hispanic MSM. In 2006, surveillance data indicated that the
overall HIV incidence rate in Puerto Rico was twice the estimated US
rate and 1.5 times higher than the estimated rate for Hispanics in the
US (54). Between 2004 and 2008, the prevalence of HIV increased from
9.13% to 11.10% among MSM in Puerto Rico, suggesting that behavioral
risks among this group might be a contributor to the continuing HIV
epidemic (55). A descriptive profile of MSM in Puerto Rico indicated
that a significant proportion (62.2%) of MSM reported vaginal sexual
practices in the last 12 months, suggesting that men who engage with
both male and female sexual partners can serve as bridge populations
(55). This is particularly important when considered in the context of
observations indicating that anal cancer incidence among HIV positive
men will not decline in the antiretroviral therapy (ART) era (56). As an
example, studies in San Francisco have demonstrated that not only has
the incidence of anal cancer among HIV-positive MSM failed to decline
since the introduction of ART, but that the incidence has continued to
increase.

The annual incidence rate for anal cancer has increased for both
men and women during the past 3 decades (57), with men showing the
highest increase. In the US, the incidence of anal cancer among men is
relatively low in the general population, with an incidence rate of 1.4
per 100,000 men. Hispanics overall have a lower incidence of anal cancer
(0.8 per 100,000) compared with non-Hispanics whites (1.4 per 100,000)
and non-Hispanic blacks (1.6 per 100,000) (58). However, incidence is
highest among MSM. According to recent data from the US and Europe, the
incidence of anal cancer among HIV-positive individuals ranges from 42
to 137 cases per 100,000 person-years, a rate that is 30 to 100 times
higher than that of the general population (59-60). In HIV-seronegative
MSM, the estimated incidence of anal cancer is 35 cases per 100,000,
estimates similar to the incidence of cervical cancer in the US before
the introduction of cervical cytology testing (61). From 1987-2004,
incidence trends of anal cancer increased in Puerto Rican men (46), with
an average annual increase of 4% per year (APC 3.2). In 2004, the
age-adjusted (US population) incidence of anal cancer in this population
was 0.73 per 100,000 (Figure 2).

[FIGURE 2 OMITTED]

Oral HPV infection and cancer

HPV is frequently associated with benign warts (oral papillomas),
as well as benign and malignant neoplasms in the oral cavity. HPV 6 and
11 are most associated with oral papillomas (62) whereas; HPV16 is the
most frequently detected HPV type in oral SCC, followed by HPV18 (63).
The prevalence of oral papillomas/warts in the US estimated in the Third
National Health and Nutrition examination survey (NHANES III) 1988-1994,
was 1.9% in non-Hispanic whites and 2.2% in both non-Hispanic blacks and
Mexican Americans (64). Meanwhile, a recent review of 18 international
studies and 4,581 healthy cancer-free individuals determined a pooled
prevalence of HPV infection of the oral cavity of 4.5% (95%
CI=3.9%-5.1%). In this study, oral HPV-16 accounted for 28% of all HPV
detected in the oral cavity, with similar prevalence of oral infection
in both men (4.6%) and women (4.4%) (65). To date, studies of oral HPV
infection specifically for Hispanics in the US are scarce. In general,
risk factors such as oral sex and open-mouthed kissing are associated
with oral HPV infection (66). Sexual behaviors are also associated with
cancer risk at the oropharyngeal sites most strongly associated with HPV
infection (67).

Oral cavity and pharyngeal cancer is the 10th most common cancer
among Hispanic men in the US (68) and the 4th most common cancer in men
in Puerto Rico (69). This cancer type is of particular relevance in
Puerto Rico as its incidence in men is among the highest in the American
region (70) and among various racial/ ethnic groups in the US (18.5 per
100,000 from 1998-2002). Oral cavity cancer includes cancer of the lip,
tongue, gum, floor of the mouth, salivary glands and palate; while
pharyngeal cancer includes cancers of the oropharynx, nasopharynx and
hypopharynx. The incidence of the disease is higher in men than in
women, a disparity probably explained by higher risk factors for the
disease among men, such as tobacco consumption (71). Although a
substantial percentage of oral and pharyngeal cancers is attributed to
alcohol and tobacco exposure, epidemiological data also provide evidence
for an independent association between HPV infection and a subset of
these tumors, particularly with HPV-16 (72-73). While oral cavity cancer
seems to be more strongly associated to alcohol and tobacco exposure
than to HPV infection, oropharyngeal cancer (base of the tongue,
oropharynx, tonsils and soft palate) seems to be more strongly
associated to HPV infection, with tonsillar SCC being the sub-site most
strongly and consistently associated with HPV.

A recent meta-analysis by IARC has confirmed HPV as an independent
risk factor for oral and oropharynx cancers (63). In this meta-analysis,
HPV was detected in 3.9% (95% CI, 2.5%-5.3%) of oral cavity tumors and
18.3% (95% CI=12.0%-24.7%) of oropharyngeal tumors (63). Meanwhile, a
recent study in Mexico showed that oncogenic-HPV was strongly associated
with oral and oropharyngeal SCC, supporting that HPV16 and HPV18 are
also risk factors for oral cancer in this population (74). In Cuba, a
country with an intermediate incidence of oropharyngeal cancer, strong
associations of the disease have been found for tobacco, alcohol
consumption, low fruit consumption (75), and HPV (63). Nonetheless, many
aspects of these associations remain to be investigated, such as the
potential interactions between HPV infection and lifestyle practices of
individuals that increase oral and pharyngeal cancer risk. All this
information is essential to better define the precise contribution of
HPV to the etiology of these tumors and for the development of
prevention interventions.

Another area of research interest is the fact that recent studies
report that molecular and epidemiological profiles suggest that
HPV-positive oropharyngeal cancer is a distinctive disease entity that
differs from HPV-negative oropharyngeal cancer (76), with different
genome-wide expression profiles and clinical outcomes. For example,
HPV-positive oropharyngeal cancer patients seem to be more responsive to
chemotherapy and radiation than HPV-negative patients (77). Further
elucidation of these differences is important for better understanding
the etiology of this disease, its prevention and management.

Although Hispanic men overall have lower rates of oral and
pharyngeal cancer than non-Hispanic men, men in Puerto Rico have a
higher incidence of the disease compared with Hispanics and non-Hispanic
whites in the US (71). They also have a higher mortality risk
(p<0.05) of the disease compared with Hispanics, non-Hispanic whites
and non-Hispanic blacks in the US (71). In 2004, the age-adjusted (US
population) incidence of oral and pharyngeal cancer in Puerto Rico was
15.48 per 100,000 (Figure 2). In the US, the annual incidence rates of
potentially HPV-associated oropharyngeal and oral cavity cancers,
specifically cancers of the tonsil and base of tongue, significantly
increased from 1998 through 2003, an average of 3% per year, whereas the
incidence rates of cancer sites not previously shown to be associated
with HPV, such as cancer of the oral tongue and larynx, generally
decreased (73). It has been suggested that increases in rates of cancer
in certain sites of the oropharynx, despite the reductions in tobacco
consumption in the US in the last decades, could be explained by HPV
infections (78). In Puerto Rico, from 1987-2003, incidence trends of
cancer of the oral cavity and pharynx decreased, with an average annual
decrease of 3.8% for men and 2.9% for women (79). These declines are
consistent with declines reported since the 1960's in Puerto Rico
(71, 80), although, like it has been studied in the US, further research
should specifically compare cancer trends between HPV-related and
non-related sub-types.

Population-based data on oral HPV infection do not yet exist for
Puerto Rico. However, various studies suggest that the population of
Puerto Rico is at high risk for oral HPV infection and potentially
HPV-related malignancies. In a case series (n=118) of patients of head
and neck SCC, HPV 16 DNA was present in 44% of the tumors, suggesting a
high prevalence of HPV 16 among the head and neck cancer population in
Puerto Rico (81). Similar results have been observed in head and neck
cancer (82) and oral SCC (83) patients in Mexico, with prevalence
estimates of HPV16 infection in 70% and 67% of tumors, respectively. In
Puerto Rico, although a substantial percentage of oral and pharyngeal
cancer is also attributed to alcohol and tobacco exposure, about one
quarter of oral cancer cases in men and approximately half of those in
women in Puerto Rico are not attributed to these exposures (84),
highlighting the relevance to explore other potential risk factors in
this population.

III. Biobehavioral and Psyschosocial Factors Related to Infection
and Vaccination

Knowledge of HPV Infection

Although there are increasing studies about HPV awareness and
knowledge, these efforts have mainly focused on women. Studies in men,
particularly among those of Hispanic origin, are scarce. In those
studies that have evaluated gender differences, it is notable that men
have lower knowledge about HPV compared with women (85). Their knowledge
is also limited in relation to the long-term consequences of HPV and
regarding its modes of transmission.

A cross-sectional household survey among men and women 15-74 years
in Puerto Rico (86) found that the percentage of people who reported to
have ever heard about HPV infection was poor, particularly for men
(17.6%). A small percentage of men interviewed in this sample were also
unaware of the existence of an HPV vaccine at the time (13.5%). This
significant lack of knowledge among Puerto Rican men raises concerns
regarding the consequences that unawareness of a highly infectious
disease will have on transmission to their female and/or male sexual
partners. Thus, results highlight the need to implement primary
preventive interventions aimed at integrating HPV screening and
education in primary health care settings.

Another study among Hispanic men and women in the Texas-Mexico
border addresses the issue of understanding the diagnosis of HPV
infection (87). In this qualitative study, men initially interpreted a
diagnosis of HPV as an indication of their partner's infidelity,
which reflects not only a lack of knowledge of HPV infection in men but
also reflects strong cultural norms within this group. This study
supports previous research findings showing that STI-associated stigma
can be a powerful barrier to STI-related information seeking, screening,
and treatment behaviors, and that these patterns may vary by ethnicity
(88-89).

Vaccine Acceptability

Despite the impact of the HPV vaccine on preventing chronic
life-threatening diseases, if men's knowledge of HPV risk is
limited, their level of interest in prophylactic vaccination can also be
expected to be low. Currently, research on HPV vaccine acceptability is
limited to cross-sectional studies, most involving small, convenience
samples (90) and with limited participation by Hispanic males.
Additionally, existing studies which evaluate the acceptability of the
vaccine in men were conducted prior FDA approval of the vaccine, leading
to a hypothetical response. In general, although most studies have found
a significant association between vaccine acceptance, high-risk
behaviors (91) and physician recommendation (92), another study reported
moderate interest in the HPV vaccine in young men, even after informing
about the benefits of male HPV vaccination in reducing cervical cancer
risk (93). Some studies have shown that Hispanic ethnicity is positively
correlated with HPV vaccine acceptability (91), but other studies have
shown no differences in vaccine acceptability by ethnicity (94).

Few research studies have examined an interaction effect between
predictors of HPV acceptability and ethnicity, with a particular
evaluation of sexual preferences. Given that acceptability rates might
not correlate directly with vaccine uptake, such information will be
important when developing sensitive educational information to increase
awareness and completion of vaccination. Finally, given that vaccination
of HPV-na'ive individuals is optimal for the vaccine to be most
clinically effective, assessing the attitudes of parents about HPV
vaccine in young boys will also be critical in order to develop
successful implementation of widespread HPV vaccination in this group
(95).

IV. Conclusion

With the world-wide introduction of two new prophylactic vaccines
against high-risk HPVs causing cervical cancer and the recent FDA
approval of one of them for men, there is an urgency to determine the
burden of the HPV epidemic in Hispanic populations before vaccine
programs are implemented on a widespread basis. Knowledge of the burden
of the disease prior to implementation of these programs will allow a
better assessment and understanding of the short-term and long-term
effectiveness of this primary prevention strategy for cervical neoplasia
and genital warts, and its potential impact in the prevention of other
HPV related malignancies, such as penile, anal and oral cancer. Of
particular interest is to examine the burden of HPV infection in US
Hispanics, and Puerto Rican men, since these are groups with underlying
social disparities associated with health status--including poverty,
limited access to quality health care, poor health-seeking, low health
literacy and high rates of behavioral risks (96). This is of particular
relevance in Puerto Rico, given that population-based data on HPV
infection do not yet exist for either men or women. In addition, given
the changing patterns of HPV-related malignancies in these groups,
research should further access the reasons for these changes in patterns
of disease occurrence, including changes in patterns of HPV infection,
sexual behaviors and/other risk factors and how they influence disease
trends. This will also be key to understanding disease epidemiology and
future population-based disease control efforts.

Research is particularly warranted among high-risk groups of
racial/ethnic minorities, such as: asymptomatic heterosexuals, HIV+
individuals and MSM. Despite the fact that significant differences
within Hispanic sub-groups have been reported both for substance use and
sexual practices (97), the available data on HPV infection in Hispanics
does not permit any assessment of potential sub-group differences within
the broad Hispanic/ Latino category. Consequently, studies of specific
subgroups are needed to disentangle intra-ethnic differences between
groups and to better focus both epidemiological research and targeted
interventions.

Given that knowledge of HPV infection among Hispanics is likely to
be relatively low, it is reasonable to assume that a necessary first
step in advancing HPV vaccination in this group will require the
development of empirically-tested initiatives that will test the best
strategies to foster positive attitudes towards vaccination. Recent
studies on other STIs, including chlamydia, syphilis, and HIV, indicate
that interventions that are tailored to specific ethnicities are more
effective (98). While encouraging, the generalizability of these
interventions for HPV knowledge and vaccine uptake in Hispanic and
Puerto Rican men remains unknown.

Although the research agenda has to be driven towards understanding
the burden of HPV infection in men, these efforts have to be in parallel
with interventions to improve knowledge of HPV and acceptability of the
HPV vaccine for two groups in particular: high-risk men and
Hispanic/Puerto Rican parents. These interventions will have to be
sensitive to cultural norms, which vary within the Hispanic/Latino
community, and across generations. Targeting these groups within the
Hispanic and Puerto Rican population might have multiple clinical and
public health benefits such as: 1) decreasing HPV infection sequelae in
men, 2) decreasing HPV infection sequelae in men's sexual partners
(both men and women), and 3) increasing heard immunity at the population
level (99).

Acknowledgments

This work was supported by the following grants from the National
Institute of Health: Support Opportunity for Addiction Research (SOAR)
(R03), [NIDA RO3 027939-01], National Institute of Allergy and
Infectious Diseases Grant 1 SC2 AI090922-01, Training in Computational
Genomic Epidemiology of Cancer (National Cancer Institute [NCI]
5R25CA094186-08), the NCI Grant U54CA96297 for the Puerto Rico Cancer
Center/ The University of Texas M. D. Anderson Cancer Center, Partners
for Excellence in Cancer Research, and the RCMI Program Grant G12RR03051
from the University of Puerto Rico. We wish to express our gratitude to
Dr. Angela Pattatucci, Director of the Center for Evaluation and
Sociomedical Research, University of Puerto Rico, Graduate School of
Public Health for her review and suggestions to this manuscript.

(5.) Gerberding JL. Report to Congress: Prevention of Genital Human
Papillomavirus Infection: Centers for Disease Control and Prevention.
2004, Center for Disease Control and Prevention. Retrieved November 11,
2008 from the World Wide Web:
http://www.cdc.gov/std/HPV/2004HPV%20report.pdf

(13.) Centers for Disease Control and Prevention. "HIV/AIDS
Among Hispanics/Latinos: Factsheet". Atlanta: Department of Health
and Human Services, Centers for Disease Control and Prevention, 2008.
http://www.cdc.gov/hiv/hispanics/resources/ factsheets/hispanic.htm.

(64.) Oral health U.S. Dental, Oral and Craniofacial Data Resource
Center of the National Institute of Dental and Craniofacial Research,
the National Institutes of Health and Division of Oral Health, National
Center for Chronic Disease Prevention and Health Promotion, the Centers
for Disease Control and Prevention. 2002. Available at
http://drc.hhs.gov/report/pdfs/ section6-oralinfections.pdf

* Center for Evaluation and Sociomedical Research, Graduate School
of Public Health, Medical Sciences Campus, University of Puerto Rico;
([dagger]) Department of Biostatistics and Epidemiology, Graduate School
of Public Health, Medical Sciences Campus, University of Puerto Rico;
([double dagger]) Cancer Control and Population Sciences Program,
University of Puerto Rico Comprehensive Cancer Center; ([section])
Department of Medicine, University of California San Francisco, San
Francisco, CA 94143 USA